This study investigates inductively coupled transmission technology using seawater and underwater anchor chains as the transmission medium for real-time data transfer from underwater measurement instruments.Because of...This study investigates inductively coupled transmission technology using seawater and underwater anchor chains as the transmission medium for real-time data transfer from underwater measurement instruments.Because of the physical properties of seawater,challenges,such as frequency selective fading and multipath effect,limit long-distance current signal transmission.Conventional modulation techniques,such as amplitude shift keying(ASK)and differential phase shift keying(DPSK),are constrained by low bandwidth utilization and high bit error rates(BER).To address these issues,we optimize the seawater channel model using data from the National Oceanographic Data Center and previous measurements,analyzing the relationship between seawater conductivity,depth,and signal frequency.We constructed an experimental platform using a six-winding manganese-zinc ferrite ring based on an inductive coupling model for data transmission.A steel cable is anchored at both ends of a seawater bucket through two rings,exposing the cable core to establish a closed loop in seawater.An orthogonal frequency division multiplexing(OFDM)algorithm is used to improve transmission performance by distributing data across multiple subcarriers,effectively mitigating multipath fading and frequency selective fading.Compared with ASK and DPSK,this method significantly reduces the BER and improves the channel capacity,exhibiting robustness in underwater communication.Finally,in our study,a mathematical model of the underwater multipath channel for distances of 300,1000,and 2000 m is established,showing an improvement in channel capacity of approximately 2.5 bps/Hz based on the OFDM algorithm.This advancement is essential for enhancing the performance of underwater signal transmission and supporting its practical application.展开更多
Brucellosis,caused by Brucella,is one of the most common zoonosis.However,there is still no vaccine for human use.Although some live attenuated vaccines have been approved for animals,the protection effect is not idea...Brucellosis,caused by Brucella,is one of the most common zoonosis.However,there is still no vaccine for human use.Although some live attenuated vaccines have been approved for animals,the protection effect is not ideal.In this study,we developed a dual-antigen nanoconjugate vaccine containing both polysaccharide and protein antigens against Brucella.First,the antigenic polysaccharide was covalently coupled to the outer membrane protein Omp19 using protein glycan coupling technology,and then it was successfully loaded on a nano-carrier through the SpyTag/SpyCatcher system.After confirming the efficient immune activation and safety performance of the dual-antigen nanoconjugate vaccine,the potent serum antibody response against the two antigens and remarkable protective effect in non-lethal and lethal Brucella infection models were further demonstrated through different routes of administration.These results indicated that the dual-antigen nanoconjugate vaccine enhanced both T helper 1 cell(Th1)and Th2 immune responses and protected mice from Brucella infection.Furthermore,we found that this protective effect was maintained for at least 18 weeks.To our knowledge,this is the first Brucella vaccine bearing diverse antigens,including a protein and polysaccharide,on a single nanoparticle.Thus,we also present an attractive technology for co-delivery of different types of antigens using a strategy applicable to other vaccines against infectious diseases.展开更多
Dividing-wall columns(DWCs)are widely used in the separation of ternary mixtures,but rarely seen in the separation of petroleum fractions.This work develops two novel and energy-efficient designs of lubricant-type vac...Dividing-wall columns(DWCs)are widely used in the separation of ternary mixtures,but rarely seen in the separation of petroleum fractions.This work develops two novel and energy-efficient designs of lubricant-type vacuum distillation process(LVDP)for the separation of hydroisomerization fractions(HIF)of a hydrocracking tail oil(HTO).First,the HTO hydroisomerization reaction is investigated in an experimental fixed-bed reactor to achieve the optimum liquid HIF by analyzing the impact of the operating conditions.A LVDP used for HIF separation is proposed and optimized.Subsequently,two thermal coupling intensified technologies,including side-stream(SC)and dividing-wall column(DWC),are combined with the LVDP to develop side-stream vacuum distillation process(SC-LVDP)and dividing-wall column vacuum distillation process(DWC-LVDP).The performance of LVDP,SC-LVDP,and DWC-LVDP are evaluated in terms of energy consumption,capital cost,total annual cost,product yields,and stripping steam consumption.The results demonstrates that the intensified processes,SC-LVDP and DWC-LVDP significantly decreases the energy consumption and capital cost compared with LVDP.DWC-LVDP further decreases in capital cost due to the removal of the side stripper and narrows the overlap between the third lube oils and fourth lube oils.This study attempts to combine DWC structure into the separation of petroleum fractions,and the proposed approach and the results presented provide an incentive for the industrial implementation of high-quality utilization of HTO through intensified LVDP.展开更多
基金supported by grants from the National Natural Science Foundation of China(No.62071329)the National Science Foundation of Tianjin(No.23JCZDJC00440)the Key Areas R&D Programs of Guangdong Province(No.2020B1111020001).
文摘This study investigates inductively coupled transmission technology using seawater and underwater anchor chains as the transmission medium for real-time data transfer from underwater measurement instruments.Because of the physical properties of seawater,challenges,such as frequency selective fading and multipath effect,limit long-distance current signal transmission.Conventional modulation techniques,such as amplitude shift keying(ASK)and differential phase shift keying(DPSK),are constrained by low bandwidth utilization and high bit error rates(BER).To address these issues,we optimize the seawater channel model using data from the National Oceanographic Data Center and previous measurements,analyzing the relationship between seawater conductivity,depth,and signal frequency.We constructed an experimental platform using a six-winding manganese-zinc ferrite ring based on an inductive coupling model for data transmission.A steel cable is anchored at both ends of a seawater bucket through two rings,exposing the cable core to establish a closed loop in seawater.An orthogonal frequency division multiplexing(OFDM)algorithm is used to improve transmission performance by distributing data across multiple subcarriers,effectively mitigating multipath fading and frequency selective fading.Compared with ASK and DPSK,this method significantly reduces the BER and improves the channel capacity,exhibiting robustness in underwater communication.Finally,in our study,a mathematical model of the underwater multipath channel for distances of 300,1000,and 2000 m is established,showing an improvement in channel capacity of approximately 2.5 bps/Hz based on the OFDM algorithm.This advancement is essential for enhancing the performance of underwater signal transmission and supporting its practical application.
基金supported by the National Key Research and Development Program of China(2021YFC2102100)the National Natural Science Foundation of China(U20A20361,32271507,81930122,and 82171819)the Beijing Postdoctoral Research Foundation(2021-ZZ-035)。
文摘Brucellosis,caused by Brucella,is one of the most common zoonosis.However,there is still no vaccine for human use.Although some live attenuated vaccines have been approved for animals,the protection effect is not ideal.In this study,we developed a dual-antigen nanoconjugate vaccine containing both polysaccharide and protein antigens against Brucella.First,the antigenic polysaccharide was covalently coupled to the outer membrane protein Omp19 using protein glycan coupling technology,and then it was successfully loaded on a nano-carrier through the SpyTag/SpyCatcher system.After confirming the efficient immune activation and safety performance of the dual-antigen nanoconjugate vaccine,the potent serum antibody response against the two antigens and remarkable protective effect in non-lethal and lethal Brucella infection models were further demonstrated through different routes of administration.These results indicated that the dual-antigen nanoconjugate vaccine enhanced both T helper 1 cell(Th1)and Th2 immune responses and protected mice from Brucella infection.Furthermore,we found that this protective effect was maintained for at least 18 weeks.To our knowledge,this is the first Brucella vaccine bearing diverse antigens,including a protein and polysaccharide,on a single nanoparticle.Thus,we also present an attractive technology for co-delivery of different types of antigens using a strategy applicable to other vaccines against infectious diseases.
基金funded by Shanghai Sailing Program (No.19YF1410800)National Natural Science Foundation of China(No. 21908056)。
文摘Dividing-wall columns(DWCs)are widely used in the separation of ternary mixtures,but rarely seen in the separation of petroleum fractions.This work develops two novel and energy-efficient designs of lubricant-type vacuum distillation process(LVDP)for the separation of hydroisomerization fractions(HIF)of a hydrocracking tail oil(HTO).First,the HTO hydroisomerization reaction is investigated in an experimental fixed-bed reactor to achieve the optimum liquid HIF by analyzing the impact of the operating conditions.A LVDP used for HIF separation is proposed and optimized.Subsequently,two thermal coupling intensified technologies,including side-stream(SC)and dividing-wall column(DWC),are combined with the LVDP to develop side-stream vacuum distillation process(SC-LVDP)and dividing-wall column vacuum distillation process(DWC-LVDP).The performance of LVDP,SC-LVDP,and DWC-LVDP are evaluated in terms of energy consumption,capital cost,total annual cost,product yields,and stripping steam consumption.The results demonstrates that the intensified processes,SC-LVDP and DWC-LVDP significantly decreases the energy consumption and capital cost compared with LVDP.DWC-LVDP further decreases in capital cost due to the removal of the side stripper and narrows the overlap between the third lube oils and fourth lube oils.This study attempts to combine DWC structure into the separation of petroleum fractions,and the proposed approach and the results presented provide an incentive for the industrial implementation of high-quality utilization of HTO through intensified LVDP.
